A PM2.5 Signal Acquisition And Transmission Device With Light Scattering Method And Bluerooth Technology

With the development of science and technology and the improvement of people's living level,PM2.5(Particulate matter 2.5)is increasingly becoming the focus.In order to facilitate real-time monitoring of the PM2.5 in surrounding environment,as well,to reduce device cost,power consumption and device volume.Based on light scattering theory,a portable PM2.5 monitoring system with a Bluetooth transceiver module is designed.The main works are as follows:(1)Photon scattering in the atmosphere was simulated by Monte Carlo method.Firstly,polarization states of reflected light for three kinds of light passing through the atmosphere,namely linearly polarized,linearly polarized at 45 degrees and right-handed circularly polarized light,were analyzed.Secondly,the polarized light passing through aerosol with particle size of 1000-1500-nm was also analyzed.Meanwhile polarization transmission under different conditions with the illumination of 460-nm and 556-nm light was also studied.Theoretical and experimental resultsshow that the polarization characteristics of reflective scattering light nearly maintain when incident light is linearly polarized;the depolarization degree of reflective scattering light increases with fog concentration increasing when incident light is linearly polarized at 45 degrees,as well as for the case of right-handed circularly polarized light.These results provide a theoretical basis for detecting PM2.5 concentration using the light scattering method.(2)A GP2Y1010 AUOF sensor and a BM77 Bluetooth module are adopted in our detection technology.This design combines the advantages of light scatter sensors,Bluetooth communication and intelligent terminal,which consists of a signal acquisition unit and a signal display unit.The signal acquisition unit transmits PM2.5 data by the Bluetooth technology;and the signal display unit is implemented with portable intelligent terminals for data display and data manipulation.Not only does it reduce device cost and power consumption,but also deal with data powerfully.The intelligent terminals with network convergence technology can also be utilized for real-time data sharing,which is potential for the establishment of big data of PM2.5 concentration.